/* var a = [1, 2, 3, 4, 4]
console.log(a.concat('b'))
console.log(typeof 'ok') */
/* function dateFormat(ms) {
  const d = new Date(ms)
  const y = d.getFullYear()
  const m = two(d.getMonth() + 1)
  const date = two(d.getDate())
  const h = two(d.getHours())
  const min = two(d.getMinutes())
  const s = two(d.getSeconds())
  return `${y}-${m}-${date} ${h}:${min}:${s}`
}
function two(num) {
  if (num < 10) {
    return '0' + num
  }
  return num
}
console.log(dateFormat(1514345477)) */
var a = [1, 2, 3, 4, 5, 6]
var b = a.concat()
b.join('-')
console.log(a)
